For some time now, it has been proposed (see, for example, the document No. U.S. Pat. No. 3,710,659 and CH-A-351 015) to provide, on a rotating tool-holder assembly, an electric actuator, typically an electric motor with corresponding mechanical transmission, for adjusting the radial tool position, for the purpose of compensating for the wear of the tool following upon the machining operations.
The object of the present invention is to provide a machining unit of the type specified above that will present an extremely simple and light structure and at the same time will guarantee a high precision of operation.